1. Field of the Invention
The present invention relates to a backhoe lock, and particularly to a lock which secures the forward/reverse lever of a backhoe or throttle control lever of an agricultural machine to the steering wheel to deter theft and vandalism.
2. Description of the Related Art
Earth moving construction equipment, such as backhoes, is commonly transported to a job site by flatbed truck and remains at the job site until the project is completed or until the machines are no longer needed. The equipment is usually left unattended at the job site at the end of the work day, and becomes a target for thieves and vandals. While the risk of theft and vandalism may be reduced by fencing in the job site and/or by providing a night watchman, such measures are expensive and not entirely effective. A convenient, economical, and easy to use locking mechanism which renders the machine inoperative for practical purposes, and that can be put in place at the end of the work day and removed at the beginning of the next day without the expenditure of significant time and effort is therefore desirable.
Lock devices specifically designed for backhoes and similar earth moving equipment have usually involved devices for keeping the stabilizer arm extended, such as a hinged cylindrical sleeve, or a semicylindrical sleeve, which can be locked around the piston of a stabilizer arm with the arm extended. Such devices are described in U.S. Pat. No. 4,373,851, issued Feb. 15, 1983 to R. J. Confoey, and U.S. Pat. No. 4,417,644, issued Nov. 29, 1983 to P. D. Brogard. U.S. Pat. No. 4,360,074, issued Nov. 23, 1982 to D. J. Parquet shows a hydraulic locking device for a backhoe having a plurality of hydraulically controlled rotary valves which keep the stabilizer arm extended to the ground.
Several devices are known for locking an automobile steering wheel or ignition lock. U.S. Pat. No. 4,008,590, issued Feb. 22, 1977 to Berkowitz et al., discloses a locking case which conforms to a steering column and covers the vehicle ignition. U.S. Pat. No. 5,920,254, issued Jul. 6, 1999 to C. Hsieh, describes a steering wheel lock with an alarm and a radio transmitter. A locking bar for a skid steer loader is described in my prior patent, U.S. Pat. No. 6,173,590, issued Jan. 16, 2001.
Still other lock devices are known for locking a floor shift gear lever, including U.S. Pat. No. 5,331,307, issued Jul. 19, 1994 to N. Eizen (mounting bracket bolted to floor near gear lever and a yoke received by holes in the bracket); U.S. Pat. No. 5,570,600, issued Nov. 5, 1996 to W. P. Hua (similar to the Eizen device, but with a U-shaped sleeve having lugs receiving the yoke or U-shaped bar); and U.S. Pat. No. 5,572,889, issued Nov. 12, 1996 to W. Ping-Hua (similar to the ""600 device, but with a cylindrical sleeve inserted over the gear shift lever).
U.S. Pat. No. 1,384,590, issued Jul. 12, 1921 to V. R. Buttone, describes a lock for locking the control levers of an automobile having a U-bar with aligned recesses, a crossbar having lugs which receive the parallel legs of the U-bar, and a locking rod disposed in the crossbar which engages recesses in the U-shaped bar and in the crossbar. U.S. Pat. No. 5,195,340, issued Mar. 23, 1993 to T. Huang, shows a lock with a U-shaped bar having legs that extend transversely through a hollow rod having a key plug assembly and a locking plate assembly disposed in the hollow rod.
None of the foregoing patents show a device for locking a steering wheel to a forward-reverse lever or throttle control lever. None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus a backhoe lock solving the aforementioned problems is desired.
The backhoe lock is a device for locking the forward-reverse lever of a backhoe to the steering wheel. The backhoe lock has a base plate having two parallel rows of posts extending from its top surface, including a group of four posts arranged substantially in a square configuration, and another pair of posts aligned linearly with opposing sides of the square but spaced apart by a distance greater than the length of a side of the square. The middle pair, of posts are notched. A lock plate has a plurality of holes defined therein in the same configuration as the posts so that the lock plate may slide over the posts. A lock mechanism is installed in the lock plate and controls a catch which engages the notches in the middle pair of posts so that the lock plate cannot be removed from the posts without inserting a key in the lock and rotating the cylinder.
Preferably the lock mechanism is spring biased and the notches in the middle pair of posts are configured so that when the key is moved into the locked position, the lock plate will slide down the posts, but is prevented from rising up the posts, after the fashion of a ratchet. In use, the backhoe lock is used to clamp and lock the forward-reverse lever and a spoke of the steering wheel in parallel relation so that movement of the steering wheel and forward-reverse lever are restricted in order to render the backhoe inoperable for practical purposes.
Although principally designed for use with a backhoe, the device is versatile enough to be used with a shooting boom forklift, articulating loaders and dump trucks, rollers, graders, mini-backhoes and excavators, agricultural equipment, and boats.
Accordingly, it is a principal object of the invention to provide a backhoe lock having a base plate and a lock plate which cooperate to lock a control lever to a steering wheel in order to deter theft and vandalism of backhoes, and other mobile equipment and machinery.
It is another object of the invention to provide a backhoe lock having a base plate with a unique configuration of posts extending from its top surface designed to accommodate both a forward-reverse control lever and a portion of a steering wheel therebetween.
It is a further object of the invention to provide a backhoe lock having a lock plate which ratchets down the guide posts of a base plate and is retained thereon until a lock mechanism is released.
Still another object of the invention is to provide a backhoe lock which is convenient, economical, and easy to use for preventing the theft or vandalism of construction machinery left unattended at a job site.
It is an object of the invention to provide improved elements and arrangements thereof for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.